KR20230102706A - Recirculation valve - Google Patents

Abstract

The recirculation valve according to the present invention is connected to a hot water supply pipe for supplying hot water generated by heating raw water to a hot water housing forming a hot water flow path provided so that hot water flows through the inside; A direct water housing that is connected to the direct water supply pipe for supplying direct water, which is raw water, to form a direct water flow path provided so that the direct water flows through the inside; a recirculation housing configured to communicate the hot water flow path and the direct water flow path to form a recirculation flow path provided to flow hot water in the hot water flow path to the direct water flow path; And a water pressure switch provided to be movable along a reference direction in the direct water housing to close or open the recirculation passage, wherein the hydraulic pressure switch includes an upstream pressurizing unit and direct water from the direct water supply pipe to the direct water flow path. When referred to as the reference direction, which is the direction flowing into the upstream pressure unit, the inner surface of the direct water housing defining the direct water flow path includes a downstream pressure unit located on the side of the reference direction of the upstream pressure unit, and the water pressure switchgear opens the recirculation flow path. and an upstream inner surface located outside the upstream pressurizing part and a downstream inner surface located on a reference direction side of the upstream inner surface, and between the upstream inner surface and the downstream inner surface is the upstream inner surface. A step corresponding to a step formed between the pressing part and the downstream pressing part is formed.

Description

Recirculation valve {RECIRCULATION VALVE}

The present invention relates to a hot water recirculation valve.

In order to always supply hot water at a temperature higher than a specific temperature, a hot water recirculation system may be implemented. In the hot water recirculation system, even in a state in which hot water is not discharged because hot water use is stopped, hot water discharged from the boiler and supplied may return to the boiler through the direct water pipe and be reheated. While the hot water is circulated so that this process is repeated, the hot water may maintain a predetermined temperature.

However, since the direct water pipe is used for recirculation of hot water, when the direct water is used at the demand side, it is necessary to prevent the hot water from flowing into the direct water pipe. In addition, even when hot water is used at the demand point, the hot water should be supplied to the demand point and discharged, not circulated.

Therefore, a recirculation valve that blocks hot water circulation when direct water or hot water is used and circulates hot water when direct water or hot water is not used is required in the hot water recirculation system.

The recirculation valve may be disposed below the faucet or the like to constitute a hot water recirculation system. However, since sufficient space is not provided at the lower side of the faucet or it is difficult to install a recirculation valve, it may be difficult to construct a hot water recirculation system, and it may have a bad aesthetic effect.

The present invention has been made to solve these problems, and to provide a recirculation valve capable of saving space.

The recirculation valve according to an embodiment of the present invention is connected to a hot water supply pipe for supplying hot water generated by heating raw water to a hot water housing for forming a hot water flow path provided so that hot water flows through the inside; A direct water housing that is connected to the direct water supply pipe for supplying direct water, which is raw water, to form a direct water flow path provided so that the direct water flows through the inside; a recirculation housing configured to communicate the hot water flow path and the direct water flow path to form a recirculation flow path provided to flow hot water in the hot water flow path to the direct water flow path; And a water pressure switch provided to be movable along a reference direction in the direct water housing to close or open the recirculation passage, wherein the hydraulic pressure switch includes an upstream pressurizing unit and direct water from the direct water supply pipe to the direct water flow path. When referred to as the reference direction, which is the direction flowing into the upstream pressure unit, the inner surface of the direct water housing defining the direct water flow path includes a downstream pressure unit located on the side of the reference direction of the upstream pressure unit, and the water pressure switchgear opens the recirculation flow path. and an upstream inner surface located outside the upstream pressurizing part and a downstream inner surface located on a reference direction side of the upstream inner surface, and between the upstream inner surface and the downstream inner surface is the upstream inner surface. A step corresponding to a step formed between the pressing part and the downstream pressing part is formed.

Accordingly, the hot water is efficiently recirculated through a small recirculation valve, and space can be saved.

1 is a conceptual diagram of a hot water recirculation system using a recirculation valve according to an embodiment of the present invention.
2 is a longitudinal cross-sectional view of a recirculation valve according to an embodiment of the present invention.
3 is an exploded perspective view of a recirculation valve according to an embodiment of the present invention.
4 and 5 are detailed views specifically showing a cross section of a portion adjacent to a pressing portion of a hydraulic opening and closing body according to an embodiment of the present invention.
Figure 6 is a perspective view of a direct water housing according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing an embodiment of the present invention, if it is determined that a detailed description of a related known configuration or function hinders understanding of the embodiment of the present invention, the detailed description will be omitted.

Also, terms such as first, second, A, B, (a), and (b) may be used to describe components of an embodiment of the present invention. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term. When an element is described as being “connected,” “coupled to,” or “connected” to another element, that element may be directly connected or connected to the other element, but there may be another element between the elements. It should be understood that may be "connected", "coupled" or "connected".

1 is a conceptual diagram of a hot water recirculation system S using a recirculation valve 1 according to an embodiment of the present invention.

Referring to FIG. 1, a hot water recirculation system (S) using a recirculation valve (1) according to an embodiment of the present invention includes a heat source (H), a recirculation valve (1), a hot water supply pipe (L1), and a direct water supply pipe (L2). ) and a recirculation pipe (L22).

The heat source (H) is a component that forms hot water by heating direct water or returned water, which is introduced raw water. Therefore, a boiler including a heat exchanger for heating direct water using at least one of sensible heat and latent heat of combustion gas through combustion of fuel may be disposed as the heat source (H). However, if it is a device capable of receiving and heating direct water or returned water to form hot water and exporting it, another device may be disposed instead of the boiler and used as the heat source (H).

The heat source H operates when the temperature of the introduced water is less than a certain temperature or the flow rate of the introduced water is less than the operating flow rate, and heats the introduced water to form hot water to be discharged. Accordingly, the operation of the heat source H may be controlled by adjusting the flow rate. For this operation, a flow sensor (not shown) capable of measuring the flow rate may be disposed in the heat source H, and a microprocessor capable of operating the heat source H according to an electrical signal generated by the flow sensor may be used. A configured controller (not shown) may be further provided.

A recirculation pipe (L22) is connected to the heat source (H), and direct water or returned water, which is raw water delivered from the direct water supply pipe (L2), may be introduced. Using this direct water or returned water as raw water, the raw water is heated by the heat source H and discharged as hot water. A hot water supply pipe (L1) is connected to the heat source (H), and hot water is discharged through the hot water supply pipe (L1).

The hot water supply pipe (L1) is a component that is connected to the heat source (H) and supplies hot water to the consumer (SD1). One end is connected to the heat source (H), the other end passes through the recirculation valve (1) and connected to Therefore, the hot water supply pipe (L1) serves to deliver hot water from the heat source (H) to the consumer (SD1). The hot water supply pipe (L1) comes from the heat source (H) and passes through the recirculation valve (1) and is connected to the consumer (SD1), or is connected to other consumers (SD2) through other hot water supply pipes (L11) branched from the hot water supply pipe (L1). Directly connected, it is possible to supply hot water to each consumer (SD1) and other consumers (SD2).

The demand source SD1 and the other demand source SD2 may be faucets capable of discharging hot water and direct water to the outside and adjusting the degree of discharge, but are not limited thereto.

The direct water supply pipe (L2) is a component that is connected to the direct water source and supplies direct water to each demand point (SD1). One end of the direct water supply pipe (L2) is connected to an external direct water source, which is a constant source for supplying direct water, to receive and flow direct water, or through other direct water supply pipes (L21) branched from the direct water supply pipe (L2) to other demand sources (SD2). ) to supply direct water. As shown, the direct water supply pipe (L2) may pass through the recirculation valve (1) before being connected to the consumer (SD1).

The recirculation pipe (L22) is connected to the direct water supply pipe (L2), and directs the direct water from the direct water source to the heat source (H) or transfers the direct water to the direct water supply pipe (L2) through a recirculation passage formed in the housing of the recirculation valve (1) to be described later. It is a component that flows the returned water to the heat source (H). Therefore, the recirculation pipe (L22) directly or indirectly connects the direct water source and the heat source (H), so that the direct water is delivered to the heat source (H). In addition, it may be generated in the recirculation passage and delivered to the heat source (H) through the direct water supply pipe (L2). That is, it is a component that delivers water to the heat source (H).

As shown, based on the direction in which direct water flows in the direct water supply pipe (L2), one end of the recirculation pipe (L22) is connected to one location of the direct water supply pipe (L2) located upstream of the point where the direct water supply pipe (L2) diverges, , The other end of the recirculation pipe (L22) is connected to the heat source (H). Therefore, the returned water flowing in the direction opposite to the direct water flow direction and returning to the one place, and the direct water flowing downstream from the direct water source and delivered to the one place are delivered to the heat source (H) through the recirculation pipe (L22) can

In order for the recirculation pipe (L22) to transfer the direct water or the returned water to the heat source (H), a pump (P) may be provided in the recirculation pipe (L22). The pump (P) pressurizes the direct water flowing in the recirculation pipe (L22) or the returned water and sends it to the heat source (H). Therefore, the pump (P) provides power to circulate the hot water of the entire hot water recirculation system (S).

The recirculation valve 1 is a component that determines whether to recirculate hot water in the hot water recirculation system S according to an embodiment of the present invention. The recirculation valve 1 is connected to the hot water supply pipe L1 and the direct water supply pipe L2, and has a recirculation passage for forming returned water by transferring the hot water received from the hot water supply pipe L1 to the direct water supply pipe L2. . Therefore, the hot water recirculation system (S) operates as follows.

Direct water is provided from the direct water source to the direct water supply pipe (L2). A portion of the direct water is provided to other consumers (SD2) through other direct water supply pipes (L21) or delivered to the consumers (SD1) through the direct water supply pipe (L2) and the recirculation valve (1). Another part of the direct water is delivered to the heat source (H) through the recirculation pipe (L22).

The heat source (H) heats the direct water to form hot water and sends it out. Some of the hot water is discharged through the other hot water supply pipe (L11) and provided to other consumers (SD2) or delivered to the consumer (SD1) through the hot water supply pipe (L1) and the recirculation valve (1). Another part of the hot water is supplied to the direct water supply pipe (L2) through the recirculation passage of the recirculation valve (1), and may be returned along the direct water supply pipe (L2) in a direction opposite to the direction in which the direct water flows.

The water returned in the reverse direction along the direct water supply pipe (L2) flows to the heat source (H) through the recirculation pipe (L22). The returned water is heated again by the heat source (H) to form hot water and sent out through the hot water supply pipe (L1).

During this recirculation process, the recirculation valve 1 controls the flow rate of recirculated hot water.

2 is a longitudinal cross-sectional view of a recirculation valve 1 according to an embodiment of the present invention. 3 is an exploded perspective view of the recirculation valve 1 according to an embodiment of the present invention.

Referring to the drawings, the recirculation valve 1 according to an embodiment of the present invention includes a housing and a hydraulic opening and closing body 40.

housing

The housing is a component that forms the exterior of the recirculation valve (1). The housing may include a hot water housing 10, a direct water housing 20, and a recycling housing 30. The open interior of the housing may include a hot water flow path 100, a direct water flow path 200, and a recirculation flow path.

The hot water passage 100 is a passage connecting two of the openings of the hot water housing 10 and communicates with the hot water supply pipe L1 for supplying hot water generated by heating the raw water to the consumer SD1, Hot water flows through Therefore, the hot water passage 100 communicates with a part of the hot water supply pipe L1 to receive hot water and discharges the hot water from the inside of the housing to the hot water consumer SD1 through another part of the hot water supply pipe L1. It includes a hot water discharge passage for supplying. The hot water supply passage and the hot water discharge passage are connected to different openings, respectively.

The hot water housing 10 is a housing that communicates with a hot water supply pipe L1 for supplying hot water generated by heating raw water to form a hot water flow path 100 . The hot water housing 10 may include a hot water supply housing 11 forming a hot water supply passage and a hot water discharge housing 12 forming a hot water discharge passage.

As shown, the extension directions of the hot water supply passage and the hot water discharge passage may not lie on a straight line with each other. Also, when a direction in which gravity acts on an object is referred to as a vertical direction, the hot water discharge passage may be located above the hot water supply passage in the vertical direction. The hot water discharge passage may extend in a vertical direction. The hot water supply passage may extend in a horizontal direction.

The recirculation passage is in communication with the hot water passage (100). Therefore, a portion of the hot water supplied through the hot water supply passage is transferred to the hot water discharge passage, and the remaining part flows into the recirculation passage in the area where the front cover is disposed, thereby entering the recycling process.

The direct water flow path 200 is a flow path through which the direct water flows through the inside in communication with the direct water supply pipe (L2) for supplying the direct water, which is raw water, to the consumer (SD1). The direct water flow path 200 supplies direct water to the inside of the housing and discharges the hot water introduced along the recirculation flow path to the outside of the housing for recirculation, and a direct water discharge path that discharges the direct water to the outside of the housing. Including euros. In addition, the direct water flow path 200 includes a direct water intermediate flow path that connects the direct water supply flow path and the direct water discharge flow path to each other, communicates with the recirculation flow path, and accommodates the hydraulic pressure switchgear 40 to be described later therein. Therefore, the direct water is transferred from the direct water supply passage to the direct water discharge passage through the direct water intermediate passage and is delivered to the consumer (SD1).

The direct water housing 20 is a housing that communicates with the direct water supply pipe (L2) for supplying raw water direct water to form the direct water flow path 200. The direct water housing 20 may include a direct water supply housing 21 forming a direct water supply passage and a direct water discharge housing 22 forming a direct water discharge passage. A direct water intermediate flow path may be formed at a location where the direct water supply housing 21 and the direct water discharge housing 22 meet.

The direct water supply passage and the direct water discharge passage are spaced apart from each other along the direction in which the direct water intermediate passage extends and communicates with the direct water intermediate passage. Therefore, they are arranged so as to cross each other, so that the direct water flowing in the direct water supply passage does not pass through the direct water intermediate flow passage or is not directly transmitted to the direct water discharge passage without being hindered by the hydraulic pressure switch 40 accommodated in the direct water intermediate flow passage. The direct water flowing in the direct water supply passage passes through the direct water intermediate flow passage and is transferred to the direct water discharge passage.

Let the direction in which direct water is introduced through the direct water supply passage is referred to as the reference direction (D1), and the direction in which direct water is discharged through the direct water discharge passage is referred to as the discharge direction (D2). A direction in which hot water is introduced through the hot water supply passage may be in an opposite direction to the reference direction D1, and a direction in which hot water is discharged through the hot water discharge passage may be parallel to the discharge direction D2. The discharge direction D2 and the reference direction D1 may be orthogonal to each other.

As shown, the direct water supply passage and the direct water discharge passage may not be placed in a straight line with each other in an extended direction. In addition, the direct water discharge passage may be located above the direct water supply passage in the vertical direction. The direct water discharge passage may extend along the vertical direction. The direct water supply passage may extend along a horizontal direction.

The direct water intermediate flow path may communicate with the recirculation flow path. Therefore, hot water is transferred from the hot water flow path 100 to the direct water intermediate flow path through the recirculation flow path, and the delivered hot water naturally flows to the direct water supply flow path and flows in the direction opposite to the direction in which the direct water flows, so that the returned water do.

The direct water housing 20 and the hot water housing 10 may be fastened using a fastener 90. The direct water housing 20 may have a direct water flange 23 connected to the direct water inlet housing and to which the fastener 90 may be fastened. The hot water housing 10 may have a hot water flange 13 to which the fastener 90 may be fastened and connected to the hot water inlet housing. The water directing flange 23 and the hot water flange 13 may be coupled to the direct water housing 20 and the hot water housing 10 by passing through the fasteners 90 through the fastening holes formed on each in a state in which the water directing flange 23 and the hot water flange 13 are in contact with each other. Fastener 90 may be a bolt, may be a plurality, may be coupled to the direct water flange 23 and the hot water flange 13 along the reference direction (D1) or the opposite direction.

A recirculation passage may be formed at a location where the direct water housing 20 and the hot water housing 10 meet. That is, the recirculation passage may be formed in a portion surrounded by the direct water flange 23 and the hot water flange 13. The recirculation housing 30 may be disposed in the space formed by the direct water flange 23 and the hot water flange 13.

In order to maintain watertightness of the recirculation passage, an annular housing packing 73 may be disposed at the boundary between the direct water flange 23 and the hot water flange 13. The housing packing 73 may be formed of a material having elasticity.

The inner surface of the direct water flow path 200 defining the direct water housing 20 may include an upstream inner surface 201, a downstream inner surface 202 and a stepped inner surface 203. The upstream inner surface 201 is a side surface located outside the upstream pressurizing part 411 when the hydraulic switch 40 is disposed at a position to open the recirculation passage, and the downstream inner surface 202 is the upstream inner surface 201 ) is the inner surface located on the reference direction D1 side. The stepped inner surface 203 may be formed between the upstream inner surface 201 and the downstream inner surface 202 while looking in the reference direction D1. The upstream inner side surface 201 and the downstream inner side surface 202 can look in a direction orthogonal to the stepped inner side surface 203 . Between the upstream inner surface 201 and the downstream inner surface 202, a step corresponding to a step formed between the upstream pressing portion 411 and the downstream pressing portion 412 to be described later is formed. Due to this shape of the inner surface, it is possible to increase the load of direct water on the downstream pressing part 412 together with the shape of the pressing part 41 to be described later. Therefore, it is possible to secure sufficient direct water load even with a small-sized valve without having to form a very large pressure portion so that the load is sufficiently applied.

The recirculation flow path is a flow path through which the hot water flow path 100 and the direct water flow path 200 communicate with each other so that hot water in the hot water flow path 100 flows into the direct water flow path 200 . The recirculation passage may be defined by the recirculation housing 30 . A bimetallic plate 50 may be disposed in the recirculation passage. The recirculation flow path may be formed open along a horizontal reference direction D1 orthogonal to the vertical direction, similar to the direct water intermediate flow path. The recirculation passage may be defined by the inlet opening 310 , the intermediate opening 320 and the discharge opening 330 .

The recycling housing 30 may include bimetallic cases 31 and 32 and an opening/closing case 33 . The bimetal cases 31 and 32 may include an upstream bimetal case 31 and a downstream bimetal case 32 located downstream of the upstream bimetal case 31 based on the flow direction of hot water in the recirculation passage. there is. The bimetallic cases 31 and 32 and the opening/closing case 33 are positioned adjacent to each other to form a recirculation passage passing through the recirculation housing 30 along the reference direction D1. The bimetallic case (31, 32) may be interposed between the direct water housing 20 and the hot water housing 10, and the opening/closing case 33 may be located on the opposite side of the reference direction (D1) of the bimetallic case (31, 32). there is. The opening and closing case 33 may be interposed between the bimetallic cases 31 and 32 and the direct water housing 20. An upstream bimetal case 31 may be interposed between the downstream bimetal case 32 and the hot water housing 10 . A downstream bimetal case 32 may be interposed between the upstream bimetal case 31 and the direct water housing 20 .

Among the sections adjacent to the hydraulic switch 40 in the recirculation passage, a discharge section, which is one section, may be a section defined by the opening/closing case 33 . The discharge section may have a shape in which a cross-sectional area cut into a plane orthogonal to the reference direction D1 increases as it goes along the reference direction D1.

The upper bimetal case 31 may include an upper case body 311 . The upper case body 311 may be formed in an annular shape to define an inlet opening 310 . The recirculation valve 1 according to an embodiment of the present invention is disposed in a groove formed on the radial outer surface of the upstream case body 311, and the outer surface of the bimetallic cases 31 and 32 and the inner surface of the hot water housing 10 It may include a case packing 72 for maintaining the watertightness of the boundary of the side. The case packing 72 is formed in an annular shape and may be formed of a material having elasticity.

The side of the upper case body 311 in the reference direction D1 may have a profile inclined radially outward with respect to the reference direction D1. The radius inner end of the upper case body 311 may have a shape protruding in a direction opposite to the reference direction D1. The inlet opening 310 may be surrounded and defined by an inner radial end of the upper case body 311 .

The recirculation valve 1 according to an embodiment of the present invention may include a strainer 82. The strainer 82 may filter foreign substances included in the hot water delivered to the recirculation passage. The strainer 82 may be composed of a porous mesh to filter out foreign substances. There may be two nets constituting the strainer 82, and the two nets may be spaced apart from each other along the left and right directions. The circumference of the strainer 82 may be interposed and fixed between the upstream case 31 and the hot water housing 10. A strainer 82 may be located upstream of the inlet opening 310 along the flow direction of hot water.

In the recirculation valve 1 according to an embodiment of the present invention, when the bimetal plate 50 is deformed so that the center moves toward the radially inner end of the upstream case body 311 to close the inflow opening 310, the bimetallic It may include a bimetal packing 71 that can contact the plate 50 . The bimetal packing 71 may be inserted into a groove formed on the opposite side of the radially inner end of the upstream case body 311 in the reference direction D1. The bimetal packing 71 is formed in an annular shape and may be formed of a material having elasticity. Since the bimetal packing 71 contacts the bimetal plate 50, watertightness between the upper case body 311 and the bimetal plate 50 may be maintained. Therefore, even if the bimetallic plate 50 covers and blocks the inlet opening 310, the impact can be absorbed and watertightness can be maintained.

The upper bimetal case 31 may include an upper case reference protrusion 312 protruding from the upper case body 311 along the reference direction D1. The upper case reference protrusion 312 may be formed in an annular shape.

The upper bimetal case 31 may include an upper case opposite protrusion 313 protruding from the upper case body 311 in a direction opposite to the reference direction D1 . The upper case opposite protrusion 313 may be formed in an annular shape. The upper case opposite protrusion 313 may surround the lower case reference protrusion 323 to be described later, and the downstream case reference protrusion 323 is inserted into the space formed by the upper case opposite protrusion 313 to the upstream bimetal case ( 31) and the downstream bimetal case 32 may be coupled.

The downstream bimetal case 32 may include a downstream case body 321 . The downstream case body 321 may be formed in an annular shape to define an intermediate opening 320 . A side surface in the reference direction D1 of the downstream case body 321 may have a radially outwardly inclined profile with respect to the reference direction D1. The radially inner end 322 of the downstream case body 321 may have a shape protruding in a direction opposite to the reference direction D1. The intermediate opening 320 may be surrounded and defined by the radius inner end 322 of the downstream case body 321 . The middle opening 320 may be located downstream of the inlet opening 310 based on the flow direction of hot water in the recirculation passage.

The lower bimetal case 32 may include a lower case reference protrusion 323 protruding from the lower case body 321 along the reference direction D1 . The downstream case reference protrusion 323 may be formed in an annular shape.

The opening/closing case 33 may include an opening/closing body 331 surrounding and defining the discharge opening 330 . An inner surface of the opening/closing body 331 may define a discharge opening 330, which is a downstream portion of the recirculation passage, based on a direction in which hot water flows in the recirculation passage.

The inner surface of the opening and closing body 331 may include a first opening and closing inner surface 3311, a second opening and closing inner surface 3312 and a third opening and closing inner surface 3313. The second opening/closing inner surface 3312 may be disposed downstream of the first opening/closing inner surface 3311 , and the third opening/closing inner surface 3313 may be disposed downstream of the second opening/closing inner surface 3312 . The first opening/closing inner side surface 3311 may have a shape in which a cross-sectional area cut by a plane orthogonal to the reference direction D1 increases along the reference direction D1. The second opening/closing inner surface 3312 may have a shape in which a cross-sectional area cut by a plane orthogonal to the reference direction D1 is maintained along the reference direction D1. The third opening/closing inner surface 3313 may have a shape in which a cross-sectional area of the third opening/closing inner surface 3313 is cut by a plane orthogonal to the reference direction D1 while going along the reference direction D1. The hydraulic packing 44 of the hydraulic pressure opening body 40, which will be described later, comes into contact with the third opening/closing inner surface 3313 to close the discharge opening 330.

The section defined by the first opening/closing inner surface 3311 may be the above-described discharge section. The degree of inclination of the first opening/closing inner surface 3311 with respect to the reference direction D1 may be smaller than the degree of inclination of the third opening/closing inner surface 3313 with respect to the reference direction D1. As the tapered discharge section is formed by the first opening/closing inner surface 3311 , hot water may be guided to a portion where the hydraulic pressure opening body 40 blocks the discharge opening 330 .

A groove is formed on the outer surface of the radius of the opening and closing body 331 to the inside of the radius, and the opening and closing packing 74 for maintaining the watertightness of the boundary between the opening and closing body 331 and the inner surface of the direct water housing 20 can be inserted. there is. The opening and closing packing 74 may be formed in an annular shape and may be formed of a material having elasticity.

The opening/closing case 33 may include an opening/closing protrusion 332 . An opening/closing protrusion 332 may protrude from a side surface opposite to the reference direction D1 of the opening/closing body 331 in a direction opposite to the reference direction D1. The opening/closing protrusion 332 may be formed in an annular shape to surround the hydraulic pressure opening/closing body 40 . An engaging opening 333 may be formed in the opening/closing protrusion 332 extending along the circumferential direction and opening along the radial direction. A locking portion 63 included in a fixing frame 60 to be described later is inserted into and hooked into the locking opening 333, so that the fixing frame 60 and the opening/closing case 33 can be coupled to each other. The hooking part 63 has an inclined plane on the outer side of the radius, the cross-sectional area of which is cut into a plane orthogonal to the reference direction D1 while going in the reference direction D1, and is inserted into the opening and closing protrusion 332 along the reference direction D1. Snap It may be coupled to the locking opening 333 in a fit manner.

Hydraulic switch (40)

4 and 5 are detailed views specifically showing a cross section of a portion adjacent to the pressing portion 41 of the hydraulic opening and closing body 40 according to an embodiment of the present invention.

The hydraulic opening and closing body 40 is a component provided to close or open the recirculation passage. The hydraulic opening and closing body 40 may be accommodated in the direct water intermediate passage and may move along the reference direction D1 and the opposite direction. The hydraulic opening and closing body 40 moves to close the recirculation passage when direct water or hot water is used, and opens the recirculation passage by moving in the direction opposite to the direction in which direct water or hot water was used when direct water or hot water is not used. do. The direction in which the water pressure switch 40 moves when using direct water or hot water is the reference direction D1, and the direction in which direct water or hot water is not used may be opposite to the reference direction D1.

The direct water pressure of the direct water source supplying direct water is higher than the internal pressure of the hot water flow path 100. Therefore, even if the internal pressure of the direct water flow path 200 is somewhat lowered because only straight water is used, it is higher than the internal pressure of the hot water flow path 100, and the hydraulic pressure switch 40 moves in the opposite direction to the reference direction D1 by direct water. A state in which the recirculation flow path is closed by being pressurized may be maintained. Even when only hot water is used, the internal pressure of the direct water passage 200, through which direct water cannot be discharged, is higher than the internal pressure of the hot water passage 100, which is pressurized by the pump P but somewhat lowered as the hot water is discharged. Therefore, the hydraulic opening and closing body 40 is pressed in the opposite direction to the reference direction D1 by direct water, so that the state in which the recirculation passage is closed can be maintained. For the same reason, even when direct water and hot water are used together, the recirculation flow path is closed by the hydraulic opening and closing body 40.

As such, since the recirculation passage is closed when hot water or direct water is used, a situation in which direct water and hot water are mixed and supplied to the consumer SD1 while having an unwanted water temperature can be prevented.

The hydraulic opening and closing body 40 may include a shaft 43 . The shaft 43 is a structural component of the hydraulic opening and closing body 40, and may extend along the reference direction D1 and be supported by the fixing frame 60. The shaft 43 may include an upstream shaft 432 and a downstream shaft 431 located in the reference direction D1 side of the upstream shaft 432 . The diameter of the downstream shaft 431 may be larger than that of the upstream shaft 432 . The shaft 43 may be formed in a cylindrical shape, but its shape is not limited thereto.

The downstream shaft 431 may be dug to the inside of the radius to form the shaft groove 433 . The pressing part fixture 45 may be coupled to the shaft groove 433 . The pressing part fixture 45 may be a 'C' shaped C-ring. The pressing part fixture 45 may be coupled to the shaft 43 at an upstream side relative to the reference direction D1 from a position where the pressing part 41 is coupled to the shaft 43 . The pressing unit 41 may be coupled to a portion of the shaft 43 including the boundary between the upstream shaft 432 and the downstream shaft 431 .

The hydraulic opening and closing body 40 may include an opening access portion 42 . The opening access portion 42 may be located on the side of the downstream pressing portion 412 in the reference direction D1. As shown, the opening access portion 42 may be integrally formed at the end of the reference direction D1 side of the upstream shaft 43, but is formed as a separate material at the end of the reference direction D1 side of the upstream shaft 43 may be combined. The opening access portion 42 may include an access cover 421 coupled to the upstream shaft 432 while covering the upstream shaft 432 . The opening access portion 42 protrudes along the reference direction D1 from the access cover 421, and the cross-sectional area cut by the plane perpendicular to the reference direction D1 at the end of the reference direction D1 increases, so that the access cover ( 421) may include an access protrusion 422 forming a groove in which the hydraulic packing 44 is inserted. The access protrusion 422 may be inserted into the discharge opening 330 when the recirculation flow path is closed by the hydraulic opening and closing body 40 . As the access protrusion 422 is inserted into the discharge opening 330, the hydraulic packing 44 surrounding the opening access portion 42 contacts the inner surface of the opening/closing case 33 to close the recirculation flow path without significant impact. there is.

The hydraulic opening and closing body 40 may include a hydraulic packing 44 . The hydraulic packing 44 surrounds the opening access portion 42 and approaches the opening so as to contact the third opening/closing inner surface 3313 around the discharge opening 330 when the hydraulic opening 40 closes the recirculation passage. It is coupled to section 42. The hydraulic packing 44 may be formed in an annular shape and may be formed of a material having elasticity. At least one of the hydraulic packing 44 and the packings described in the specification of the present invention may be an O-ring.

The recirculation valve 1 according to an embodiment of the present invention may include an elastic member 81. One end of the elastic member 81 may be connected to the hydraulic opening and closing body 40, and the other end may be connected to the fixed frame 60. The end of the elastic member 81 on the reference direction D1 side is coupled to the access cover 421 of the opening access part 42, and the end of the elastic member 81 on the opposite side of the reference direction D1 is attached to the fixed frame 60. By being coupled, the elastic member 81 can support the water pressure opening body 40 so as to swing with respect to the fixing frame 60 . The access cover 421 may have an end on the reference direction D1 side protruding radially outward so that the elastic member 81 does not deviate in the reference direction D1. The elastic member 81 may be a spiral spring, but its type is not limited thereto.

The elastic member 81 may have a basic length that is neither stretched nor compressed when direct water or hot water is not used. When the length of the elastic member 81 is the basic length, let's assume that the place where the water pressure opening body 40 is located inside the straight water intermediate flow passage is the basic position. That is, the elastic member 81 has a basic length when the above-described condition is satisfied, and positions the hydraulic opening and closing body 40 in the basic position. In the basic position, the hydraulic opening and closing body 40 may not close the recirculation passage.

When using direct water or hot water, the elastic member 81 may be stretched by the force of direct water pressing and moving the water pressure opening body 40 . The hydraulic opening and closing body 40 may close the recirculation passage by moving in the reference direction D1, which is a direction closer to the recirculation passage by the water pressure of the direct water. At this time, the elastic member 81 having one end coupled to the hydraulic opening and closing body 40 is tensioned because the other end is connected to the fixed frame 60, but the fixed frame 60 does not move, and the elastic member 81 is elastic. The restoring force by the pressure acts on the hydraulic switch 40 in the direction opposite to the reference direction D1. Therefore, when the use of direct water ends and the external force acting on the hydraulic switchgear 40 in addition to the restoring force disappears or the rest of the external forces form an equilibrium state, the hydraulic switchgear 40 can be returned to the basic position by the restoring force.

The hydraulic opening and closing body 40 includes a pressing part 41 . The pressing part 41 is a part that is pressed in the reference direction D1 by the flowing water. The pressing portion 41 is penetrated by the shaft 43 and may be coupled to the shaft 43 . The shaft 43 may be inserted into the shaft insertion hole 410 formed in the pressing portion 41 along the reference direction D1. Therefore, the opposite end of the shaft 43 in the reference direction D1 may protrude more toward the opposite side in the reference direction D1 than the pressing part 41 . The length of the shaft 43 protruding in the reference direction D1 based on the pressing part 41 may be greater than the length of the shaft 43 protruding in the opposite side of the reference direction D1. The pressing part 41 may include an upstream pressing part 411 and a downstream pressing part 412 connected to the upstream pressing part 411 . The downstream pressing part 412 is located on the reference direction D1 side of the upstream pressing part 411 .

A cross-sectional area of the downstream pressing unit 412 cut by a plane orthogonal to the reference direction D1 may be smaller than the cross-sectional area of the direct water housing 20 obtained in the area where the downstream inner surface 202 is formed. The cross-sectional area of the upstream pressing portion 411 may be smaller than the cross-sectional area of the direct water housing 20 obtained in the region where the upstream inner surface 201 is formed. Therefore, the downstream pressing part 412 is spaced radially inward from the downstream inner surface 202, and the upstream pressing part 411 is spaced radially inward from the upstream inner surface 201 to form a spaced-apart space so that direct water flows through the spaced space. can make it fluid.

The upstream pressing part 411 and the downstream pressing part 412 are formed with different cross-sectional areas cut by a plane orthogonal to the reference direction D1, so that there is a step difference at the boundary between the upstream pressing part 411 and the downstream pressing part 412. can be formed A step corresponding to a step formed between the upstream pressing part 411 and the downstream pressing part 412 may be formed between the upstream inner surface 201 and the downstream inner surface 202 . The pressing part 41 may be formed such that the cross-sectional area of the downstream pressing part 412 is larger than the cross-sectional area of the upstream pressing part 411 . Therefore, the inner surface of the direct water housing 20 may be formed so that the cross-sectional area of the downstream inner surface 202 is also larger than the cross-sectional area of the upstream inner surface 201. When looking at the direct water housing 20 in the opposite direction of the reference direction D1, the profile of the upstream inner surface 201 may be located within the profile of the downstream inner surface 202. Due to the step difference between the upstream pressing part 411 and the downstream pressing part 412, the straight water that primarily presses the upstream pressing part 411 along the reference direction D1 is secondarily based on the downstream pressing part 412. By applying pressure along the direction D1, the pressing unit 41 can operate by receiving sufficient pressing force.

In a state in which the hydraulic opening and closing body 40 opens the recirculation passage, the downstream pressing unit 412 may be located on the reference direction D1 side of the upstream inner surface 201 . The downstream pressing part 412 may be located on the side of the step inner surface 203 in the reference direction D1.

The hydraulic opening and closing body 40 may include a vortex forming part 46 formed by digging a side surface opposite to the reference direction D1 of the downstream pressing part 412 along the reference direction D1. The radius inner boundary of the vortex forming part 46 may continue from the upstream pressing part 411 . The vortex forming unit 46 may have an annular profile when viewed along the reference direction D1. As shown in FIG. 5 by the vortex forming unit 46, a vortex may be formed from the inflowing direct water. As the vortex is formed, the force applied to the downstream pressing part 412 by direct water may increase.

The vortex forming unit 46 may be divided into two parts. The vortex-forming part 46 may include an outer vortex-forming part 461 and an inner vortex-forming part 462 . The inner vortex forming part 462 may be formed surrounding the shaft insertion hole 410, and the outer vortex forming part 461 is formed on the outer side of the inner vortex forming part 462 based on the radial direction of the downstream pressing part 412. , and may be formed surrounding the inner vortex forming part 462 when viewed in the reference direction D1. The outer vortex-forming part 461 and the inner vortex-forming part 462 may be distinguished from each other.

The pressing part 41 may include an upstream groove 48 . The upstream groove 48 may be formed by recessing a side surface opposite to the reference direction D1 of the upstream pressing part 411 along the reference direction D1. The upstream groove 48 may be formed in an annular shape surrounding the shaft insertion hole 410 when viewed along the reference direction D1.

The pressing portion 41 may include a taper pressing portion 413 . The taper pressing part 413 may be connected to the opposite side of the upstream pressing part 411 in the reference direction D1. The taper pressing portion 413 may have a shape in which a cross-sectional area cut by a plane orthogonal to the reference direction D1 increases while going in the reference direction D1. The taper pressing part 413 may contact the pressing part fixture 45 . The taper pressing unit 413 may be coupled to the upstream shaft 432 .

Figure 6 is a perspective view of the direct water housing 20 according to an embodiment of the present invention.

When the water pressure switch 40 moves along the direction opposite to the reference direction D1, the straight water housing 20 may include a stopper 24 so as to be the limit. The stopper 24 may be formed to protrude from the step inner surface 203 along the reference direction D1 so that the downstream pressurizing part 412 can touch it when the hydraulic opening 40 opens the recirculation passage. The stopper 24 may be formed in plurality and disposed spaced apart from each other. As the stopper 24 is disposed, hot water is flowing through the recirculation passage, so that the direct water passage 200 is applied to the pressurization part 41 of the hydraulic switchgear 40 even when the hydraulic switch 40 opens the recirculation passage may not be closed by

The hydraulic opening and closing body 40 may include a recessed portion 47 formed by digging a side surface of the downstream pressing portion 412 of the pressing portion 41 in the reference direction D1 in a direction opposite to the reference direction D1. The depression 47 can be divided into two parts. The depressed portion 47 may include an outer depressed portion 471 and an inner depressed portion 472 . The inner recessed portion 472 may be formed surrounding the shaft insertion hole 410, and the outer recessed portion 471 is located outside the inner recessed portion 472 based on the radial direction of the downstream pressing portion 412, When viewed in a direction opposite to the reference direction D1, it may be formed surrounding the inner recessed portion 472. The outer recessed portion 471 and the inner recessed portion 472 may be distinguished from each other.

The inner recessed portion 472 is an inner depth recessed portion formed by further recessing the inner base recessed portion 4721 and the surface opposite to the reference direction D1 of the inner base recessed portion 4721 in the direction opposite to the reference direction D1. (4722).

As the depression 47 is formed, when the hot water is recirculated, the hot water collides with the depression 47 to form a turbulent flow, and the degree of pressing the pressing portion 41 in the opposite direction to the reference direction D1 is It can be stronger than when there is no part 47. Therefore, the hydraulic opening and closing body 40 can easily open the recirculation passage. The depression 47 is divided into two parts, so that the turbulence can be formed better.

fixed frame(60)

The recirculation valve 1 according to an embodiment of the present invention may include a fixing frame 60. The fixing frame 60 is a component for fixing the hydraulic opening and closing body 40 to the housing. The fixed frame 60 may be coupled to the recycling housing 30. Since the recycling housing 30 can be coupled to the direct water housing 20, the fixed frame 60 can be coupled to the direct water housing 20 via the recycling housing 30. The fixing frame 60 is a reference direction (D1) of the outer body 61 of the frame outer body 61 to be described later to be coupled to the above-described hooking portion 63 to be coupled with the recycling housing 30 on the opposite side of the reference direction (D1) of the recirculation housing (30) can have at the end. The fixing frame 60 may be located in the reference direction D1 side of the downstream pressing part 412 .

The hydraulic opening and closing body 40 may be inserted into the fixed frame 60 along the reference direction D1. The fixed frame 60 may include a frame outer body 61 and a frame inner body 62 . Frame outer body 61 may be in contact with the direct housing 20, may be formed in an annular shape when viewed along the reference direction (D1). The frame inner body 62 may be located inside the radius of the frame outer body 61, may be connected to the frame outer body 61, may be formed in an annular shape when viewed along the reference direction (D1). A downstream shaft 431 may be inserted into the frame inner body 62 . An end opposite to the reference direction D1 of the elastic member 81 may be coupled to the frame inner body 62 .

The fixed frame 60, the opening/closing case 33, and the hydraulic opening/closing body 40 have the above-described coupling relationship, so that a recirculation module including them can be formed, and assemblability is improved by modularized parts, the recirculation valve ( 1) can be easily maintained, repaired and repaired.

Bimetal plate(50)

A bimetal plate 50 is further provided in the recirculation passage. The bimetallic plate 50 may be deformed according to the water temperature of the hot water to open the recirculation passage when the temperature of the hot water is lower than the reference temperature and close the recirculation passage when the temperature of the hot water is higher than the reference temperature. The bimetal plate 50 may open and close the inlet opening 310, which is a part of the recirculation passage.

The bimetal plate 50 may be made of a bimetal whose shape changes depending on the temperature. A bimetal is a member formed in a state in which two metals having different thermal expansion coefficients come into contact and both ends are coupled, and the two metals expand or contract at different rates depending on the temperature, changing the direction and degree of bending. Accordingly, the shape of the bimetallic plate 50 may change according to the water temperature of hot water flowing in the housing of the recirculation valve 1 .

In an area adjacent to the edge of the bimetal plate 50, a plurality of bimetal holes 500, which are holes formed by penetrating the bimetal plate 50, may be spaced apart from each other by a predetermined distance. Therefore, the hot water flowing through the inlet opening 310 can pass through the bimetal plate 50 through the bimetal hole 500 and is discharged to the direct water passage 200 through the middle opening 320 and the discharge opening 330. It can be.

The bimetallic plate 50 is disposed to be spaced apart from the inflow opening 310 when the water temperature of the hot water is lower than the reference temperature, and may contact the inflow opening 310 above the reference temperature to close the recirculation passage. Specifically, the bimetal plate 50 is deformed when the water temperature of the hot water is less than the reference temperature and departs from the bimetal packing 71 surrounding the inlet opening 310, and is deformed above the reference temperature to contact the bimetal packing 71. Accordingly, the bimetallic plate 50 may open the recirculation passage when the temperature of the hot water is less than the reference temperature and close the recirculation passage when the temperature of the hot water is greater than or equal to the reference temperature.

In more detail, focusing on the shape in which the bimetal plate 50 is deformed, when the water temperature of the hot water is less than the reference temperature, the convex shape from the hot water flow path 100 toward the direct water flow path 200, that is, the reference direction (D1) The bimetallic plate 50 may be curved in a convex shape along the opposite direction. Conversely, when the water temperature of the hot water is higher than the reference temperature, the bimetal plate 50 may be curved in a convex form from the direct water flow passage 200 toward the hot water flow passage 100, that is, in a convex form along the reference direction D1. By being deformed to have such a shape, a flow path through which hot water can flow may be formed between the bimetal plate 50 and the inflow opening 310 or the inflow opening 310 may be closed. When the water temperature of the hot water is equal to or higher than the reference temperature, the center of the bimetal plate 50 moves toward the bimetal packing 71, so that the inlet opening 310 can be closed by contacting the bimetal packing 71.

However, when the water temperature of hot water is less than the reference temperature, the bimetal plate 50 is convex along the opposite direction of the reference direction D1, and above the reference temperature, the bimetal plate 50 is deformed into a flat plate shape orthogonal to the reference direction D1. and the recirculation flow path may be closed.

In the above, even though all components constituting the embodiment of the present invention have been described as being combined or operated as one, the present invention is not necessarily limited to these embodiments. That is, within the scope of the object of the present invention, all of the components may be selectively combined with one or more to operate. In addition, terms such as "comprise", "comprise" or "having" described above mean that the corresponding component may be present unless otherwise stated, and thus exclude other components. It should be construed as being able to further include other components. All terms, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention belongs, unless defined otherwise. Commonly used terms, such as terms defined in a dictionary, should be interpreted as being consistent with the contextual meaning of the related art, and unless explicitly defined in the present invention, they are not interpreted in an ideal or excessively formal meaning.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

1: Recirculation valve
10: hot water housing
11: hot water supply housing
12: hot water discharge housing
13: hot water flange
20: direct water housing
21: direct water supply housing
22: direct water discharge housing
23: direct water flange
24 : Stopper
30: recycling housing
31: upper bimetal case
32: downstream bimetal case
33: opening and closing case
40: hydraulic switchgear
41: pressing part
42: opening access
43: shaft
44: hydraulic packing
45: pressing part fixture
46: vortex forming unit
47: depression
48: upstream home
50: bimetal plate
60: fixed frame
61: frame outer body
62: frame inner body
63: hanging part
71: bimetal packing
72: case packing
73: housing packing
74: opening and closing packing
81: elastic member
82: strainer
90: fastener
100: hot water flow
200: direct water flow
201: upstream inner side
202: downstream inner side
203: stepped inner side
310: inflow opening
311: upper case body
312: upper case reference protrusion
313: upper case opposite protrusion
320: middle opening
321: downstream case body
322: radial inner end of the downstream case body
323: lower case reference protrusion
330: discharge opening
331: opening and closing body
332: opening and closing protrusion
333: locking opening
410: shaft insertion hole
411: upstream pressing unit
412: downstream pressing unit
413: taper pressing part
421: access cover
422: access protrusion
431: downstream shaft
432: upstream shaft
433: shaft groove
461: outer vortex forming unit
462: inner vortex forming unit
471: outer depression
472: inner depression
500: bimetal hall
3311: first opening and closing inner side
3312: second opening and closing inner surface
3313: third opening inner side
4721: inner base depression
4722: inner depth depression
D1: reference direction
D2: discharge direction
H: heat source
L1: hot water supply pipe
L11: Other hot water supply pipe
L2: direct water supply pipe
L21: Other direct water supply pipe
L22: recirculation pipe
P: pump
S : Hot water recirculation system
SD1: Demand
SD2: Other sources of demand

Claims (14)

A hot water housing communicating with a hot water supply pipe for supplying hot water generated by heating raw water to form a hot water flow path through which hot water flows;
A direct water housing that is connected to the direct water supply pipe for supplying direct water, which is raw water, to form a direct water flow path provided so that the direct water flows through the inside;
a recirculation housing configured to communicate the hot water flow path and the direct water flow path to form a recirculation flow path provided to flow hot water in the hot water flow path to the direct water flow path; and
Including a hydraulic opening and closing body provided to be movable along the reference direction in the direct water housing to close or open the recirculation passage,
The water pressure opening body includes an upstream pressurizing part and a downstream pressurizing part located on the side of the reference direction of the upstream pressurizing part when the reference direction is a direction in which direct water flows from the direct water supply pipe into the direct water passage,
The inner surface of the direct water housing defining the direct water flow path includes an upstream inner surface located outside the upstream pressurizing unit when the water pressure switchgear is disposed at a position opening the recirculation flow path, and a reference direction side of the upstream inner surface. Including the downstream inner side located at,
A step difference corresponding to a step formed between the upstream pressing part and the downstream pressing part is formed between the upstream inner surface and the downstream inner surface. According to claim 1,
A cross-sectional area of the downstream pressing part cut by a plane orthogonal to the reference direction is formed larger than that of the upstream pressing part. According to claim 2,
In a state in which the hydraulic opening and closing body opens the recirculation passage, the downstream pressurizing portion is located on the reference direction side of the upstream inner surface. According to claim 2,
The hydraulic opening and closing body further includes a vortex forming part formed by digging a side surface opposite to the reference direction of the downstream pressing part along the reference direction. According to claim 2,
The hydraulic opening and closing body further includes a depression formed by digging a side surface of the downstream pressure unit in a reference direction in a direction opposite to the reference direction. According to claim 5,
The recirculation valve, wherein the recessed part includes an inner recessed part and an outer recessed part separated from the inner recessed part and surrounding the inner recessed part. According to claim 1,
When looking at the direct water housing in a direction opposite to the reference direction, the profile of the upstream inner surface is located within the profile of the downstream inner surface, the recirculation valve. According to claim 7,
The straight water housing is formed along the reference direction from the inner surface of the step formed between the upstream inner surface and the downstream inner surface facing the reference direction so that the downstream pressing part can be reached when the hydraulic pressure switchgear opens the recirculation passage. A recirculation valve comprising a stopper formed by protruding. According to claim 1,
The hot water flow path is formed so that hot water flows in a direction opposite to the reference direction, the recirculation valve. According to claim 1,
The direct water passage is formed so that the direct water is discharged along one direction orthogonal to the reference direction,
The hot water passage is formed so that hot water is discharged in a direction parallel to the direction in which the direct water is discharged, the recirculation valve. According to claim 1,
The hydraulic opening and closing body,
an opening access portion located on the side of the reference direction of the downstream pressing portion; and
The recirculation valve of claim 1, further comprising a hydraulic packing coupled to the opening approach portion and surrounding the opening access portion so as to contact a periphery of the discharge opening that is a part of the recirculation passage when the hydraulic pressure opening and closing body closes the recirculation passage. According to claim 1,
The recirculation valve further comprises a fixing frame coupled to the recirculation housing, inserted into the hydraulic opening and closing body along a reference direction, and positioned at a side of the reference direction of the downstream pressing part. According to claim 1,
The recirculation valve, wherein the discharge section, which is one section of the sections located adjacent to the hydraulic switchgear of the recirculation passage, has a shape in which a cross-sectional area cut by a plane orthogonal to the reference direction increases as it goes along the reference direction. According to claim 1,
A recirculation valve further comprising a bimetal plate that is deformed according to the water temperature of the hot water to open and close an inlet opening that is a part of the recirculation passage.

Images